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From: pxw@augean.ua.OZ.AU (Paul Whitbread)
Newsgroups: comp.lang.postscript
Subject: Color Images in PostScript
Summary: Raw Color PostScript to Tek Phaser
Keywords: Help, Color,PostScript, Images.
Message-ID: <1031@augean.ua.OZ.AU>
Date: 11 Apr 91 14:15:34 GMT
Organization: Engineering Faculty, University of Adelaide, Australia
Lines: 38

Firstly, apologies if this is a regular topic in this group.  I'm afraid that
I've considered the subject of this news group to be too esoteric in the past,
and have only recently felt game to write raw postscript.

I have been printing 8-bit grey level images on the Apple Laserwriter
by simply appending a header and trailer to my raw (byte) file. The
header contains suitable values to make the "image" command of p/s
print the image using the laserwriter's default half tone screens.

Recently, I have gained access to a color postscript printer -- the
Tektronics Phaser II, which, like the Apple laserwriter, is intended to
be used from Macintosh applications and comes with no details of how to
send it color postscript.

I have examined the three postscript books that I have (red green and blue)
and their mention of color is sparce. In particular they describe the
setrgbcolor and sethsbcolor commands and thats it.  I tried sending the
printer 3 band separations, preceded by the appropriate setcolor command,
and only a showpage right at the end.  This produces a monochrome output.

There is a hint in the red book that there is another way, but its followed
by a comment about "beyond the scope of this book".

There must be more information around, but I'm afraid I haven't got it at this
time.  Would some kind soul tell me how to get a color image -- preferably
from the separations -- and also what manuals/ref books I can look in to
find more on this subject?

Many Thanks,
Paul Whitbread
pxw@augean.ua.oz.au


-- 
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"For every difficult and complex problem there is a simple
 and incorrect answer"
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